Ron Paul is used to receiving passionate reactions from the audience when he talks about Iran and foreign policy at Republican debates, and it was no different in Mesa, Arizona Wednesday night.

The Texas libertarian received boos when he first started speaking out against military action on Iran, who much of the International community fears is developing a nuclear weapon. At the end of his rant, however, Paul received cheers.

Now, if you're so determined to go to war, the only thing that I plead with you for, if this is the case, is do it properly, Paul said, in response to the question posed by CNN's John King. Ask the people and ask the Congress, and ask for a declaration of war. This is war and people are going to die and you have got to get a declaration of war.

Paul, an Air Force veteran, who has been very vocal in his opposition to the Iraq war, having troops in Afghanistan, going into Libya and getting involved in overseas affairs, was the only candidate on stage who said going to war with Iran should be off the table. Rick Santorum, Newt Gingrich and Mitt Romney all agreed that the Middle Eastern country was a threat to both America's and Israel's safety.

As soon as Paul began talking about the issue, a few boos could be heard from the audience.

We don't know if they have a weapon. As a matter of fact there's no evidence that they have it, there is no evidence--Israel claims they do not have it, and our government doesn't.

Paul went on to argue that going to war with Iran would backfire.

I don't want them to get a weapon, but what I think is what they're doing is encouraging them to have a weapon because they feel threatened. If you look at a map of Iran, we have 45 bases around the country plus submarines, the Iranians can't possible attack anybody. We're worrying about the possibility of one nuclear weapon.

Just think about the Cold War. The Soviets had 30,000 of them, and we talked to them. The Soviets killed 100 million people, and the Chinese, and we worked our way out of it. And if you want to worry about nuclear weapons, worry about the nuclear weapons that were left over from the Soviet Union. They're still floating around. They don't have it all detailed. So we're ready to go to war...I say going to war rapidly like this is risky and it's reckless.

The Texas congressman also pointed to Fidel Castro, the autocratic leader of Cuba that the U.S. had tried to overthrow in the 60s. Fifty years, and Castro is still there. It doesn't work.

The other candidates completely disagreed with Paul and blasted President Obama for not standing up to Iran's threats. Gingrich, former speaker of the House, said the U.S. should take Iran seriously, especially because President Ahmadinejad says he does not believe in the Holocaust and wants to wipe Israel off the map.

I'm inclined to believe dictators, I think it's dangerous not to, Gingrich said.

Below is video from the debate. Ron Paul begins speaking about two minutes in.